Cancelling one intermediate segment on international UA flight
Planning a UA international flight, revenue ticket (P booking class), Europe, USA, Mexico, USA, Europe.
I still have some uncertainty in my itinerary, which I can plan for easily if I would be able to cancel one or two segments of the ticket (after first segment used). This would make the round trip into an open jaw, which is ok with the fare rules. Specifically, instead of MEX IAD PHX EWR where PHX begins the return trip, it would become MEX -open jaw- PHX EWR
As long as I do this at least a few hours before the flight - can I cancel one or two segments without changing the rest of the trip?
Any other comments or advice please?